Statistical Mechanics Theory of Ion Channel

本研究的目的是构建一种新的理论来详细描述离子通道的传导机制和离子选择性。研究的主要结果如下。(1)对钾离子通道(KCSA)选择性滤膜中水和离子(Li+、Na+、K+)分布的三维分析表明，所有离子都结合在滤膜区域，结合方式各不相同，离子选择性来源于结合方式的不同。(2)将3D-RISM理论与广义朗之万理论相结合，得到了描述通道蛋白结构涨落的新方程，该方程在通道的门控中起着关键作用。

The purpose of the study is to construct a new theory to describe the conduction mechanism and the ion selectivity of the ion channels in molecular detail. Main results of the study are as follows. (1) Analyses based on 3D-RISM for the distribution of water and ions (Li+, Na+, K+) in the selective filter of the potassium channel (KcsA) have revealed that all the ions are bound in the filter region, that the binding modes are quite different from each other, and that the ion selectivity is originated from the difference in the binding modes. (2) We have derived new equations to describe the structural fluctuation of channel protein, which play crucial role in the gating of a channel, combining the 3D-RISM theory with the generalized Langevin theory.